What's being called the Brexit sent shockwaves through U.S. stock exchanges. The Dow, Nasdaq and S&P 500 all ended the day down. The biggest hit was to the Dow, which ended down more than 600 points.

According to one ABC analyst, the average 401(k) lost about $2,700 on Friday as deeply intertwined global markets reacted to Britain's decision to disconnect.

Simon Keeling is a financial adviser for Edward Jones in Concord. He's also a native of Doncaster, England, and he said he has been keeping a close eye on the Brexit vote.

"I had friends and family back home that voted on both sides," he said. "I went to bed last night, and the exit polls were indicating that we were going to be staying in."

Keeling said he has been explaining the consequences of the vote to his clients.

"The thing the markets do not like is surprises and uncertainty, and that's unfortunately where we are at the moment," he said.

Financial analyst Marc Hebert of The Harbor Group said he thinks the volatility will continue into next week.

"The advice would be to just stick with the program, because if you're allocated properly for whatever your personal goals and objectives are, there's no reason to change," he said.

Hebert said he thinks nerves will settle as markets gain more certainty about what the vote really means.

"I think this is a short-term blip in the markets trying to figure out what's going to happen moving on in the future," he said.

Keeling said he also expects a rebound, but he said investors should be aware that it's going to take time for Great Britain to separate itself from the EU.

"We could be hearing about this for another one to three years," Keeling said. "Britain now has got to kind of renegotiate their trade and economic relationships. That's not going to happen overnight."

Friday was the worst trading day for the U.S. in 10 months, erasing more than $800 billion in market value.